Network Working Group O. DeLong
Internet-Draft DeLong Consulting
Category: Informational
March 2013
ULA IPv6 Address Prefix Reserved for Documentationdraft-delong-ula-example-00
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Abstract
To reduce the likelihood of conflict and confusion when relating
documented examples to deployed systems, an IPv6 Unicast Address
prefix is reserved for use in examples in RFCs, books, documentation,
and the like.
Since the publication of [RFC 4193] (ULA), it is necessary to
provide examples of ULA addresses in various documents, including
some Internet-Drafts currently under consideration.
This draft seeks to add ULA prefixes reserved for documentation
purposes similar to the GUA reservation specified in [RFC3489]
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 29, 2013.
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Internet-Draft ULA Documentation Prefix March 2013
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents.
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction.....................................................22. Acknowledgements.................................................23. Documentation IPv6 Unique Local Address Prefix...................34. Operational Implications.........................................35. IANA Considerations..............................................36. Security Considerations..........................................37. References.......................................................47.1. Normative References.........................................47.2. Informative References.......................................4
Authors' Addresses..................................................41. Introduction
[RFC 4193] does not specify a ULA prefix to be used for
documentation purposes. For the same reasons an IPv6 Global
Unicast Prefix (GUA) is needed for documentation in [RFC 3849],
there is also need for a ULA prefix.
Whereas [RFC 3849] delegates 2001:db8::/32 to be used for
documentation purposes where an IPv6 GUA prefix or address
is needed, this memo proposes designating two /48s from
ULA space for that purpose when an example of ULA is needed.
2. Acknowledgements
This draft is a logical extension of the work in [RFC 3849] and
I wish to thank and acknowledge the contributions of its authors
Geoff Huston, Anne Lord, and Phil Smith.
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Internet-Draft ULA Documentation Prefix March 20133. Documentation IPv6 ULA Prefix
To allow documentation to accurately describe deployment examples,
the use of site local or link local addresses is inappropriate, and a
unicast address block is required. While there is Global Unicast
space designated for Documentation in [RFC 3849], no such provision
exists within the ULA prefix (fc00::/7) for either random (fd00::/8)
or registered (fc00::/8).
Since 2001:db8::/32 was designated for documentation purposes in
[RFC 3849] and is widely and readily recognized as such throughout
the networking community, this memo suggests the use of similar
ranges within the ULA prefixes for that same purpose. The proposed
prefixes are fc00:2001:db8::/48 (ULA Registered) and
fd00:2001:db8::/48 (ULA Random), respectively.
In the case of fc00:2001:db8::/48 this would serve only as a
statement of intent until such time as the use of fc00::/8 is
documented by the IETF.
4. Operational Implications
This assignment implies that IPv6 network operators should not
use these prefixes in their actual deployments of IPv6 ULA.
Further it implies that these prefixes should be specifically
filtered in any situation where overlapping ULA prefixes may be
otherwise permitted by route or packet filters.
This is not a local-use prefix, and the filters may be used in
both local and public contexts, though in the public context, a
more general filter of all ULA space (fc00::/7) may be more
desirable. In general, the combination of the specific and more
generic filter together should, while unnecessary, not have
any harmful effects.
5. IANA Considerations
IANA is to record the allocation of the IPv6 ULA prefixes
fc00:2001:db8::/48 and fd00:2001:db8::/48 as additional
documentation-only prefixes in the IPv6 address registry.
No end party is to be assigned these addresses.
6. Security Considerations
IPv6 addressing documents do not have any direct impact on Internet
infrastructure security.
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Internet-Draft ULA Documentation Prefix March 20137. References7.1. Normative References
[RFC3849] Huston, G., Lord, A., and Smith, P., "IPv6 Address Prefix
Reserved for Documentation", RFC 3849, July 2004.
7.2. Informative References
[RFC4193] Hinden, R. and Haberman, B., "Unique Local IPv6 Unicast
Addresses", RFC 4193, October 2005.
Authors' Addresses
Owen DeLong
DeLong Consulting
EMail: owen@delong.com
Full Copyright Statement
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents carefully,
as they describe your rights and restrictions with respect to this
document. Code Components extracted from this document must include
Simplified BSD License text as described in Section 4.e of the Trust
Legal Provisions and are provided without warranty as described in the
Simplified BSD License.
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Internet-Draft ULA Documentation Prefix March 2013
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.